Journal of Comparative Physiology B

, Volume 179, Issue 2, pp 155–164 | Cite as

Daily rhythmicity and hibernation in the Anatolian ground squirrel under natural and laboratory conditions

  • Mutlu Kart Gür
  • Roberto RefinettiEmail author
  • Hakan Gür
Original Paper


We studied daily rhythmicity of body temperature (T b) before and during hibernation in Anatolian ground squirrels (Spermophilus xanthoprymnus) under natural and laboratory conditions using surgically implanted temperature loggers. Under both conditions, robust daily T b rhythmicity with parameters comparable to those of other ground squirrel species was observed before but not during hibernation. Euthermic animals had robust daily T b rhythms with a mean of 37.0°C and a range of excursion of approximately 4°C. No T b rhythm was detected during torpor bouts, either because T b rhythmicity was absent or because the daily range of excursion was smaller than 0.2°C. The general patterns of hibernation that we observed in Anatolian ground squirrels were similar to those previously observed by other investigators in other species of ground squirrels.


Circadian rhythm Hibernation Body temperature Torpor Spermophilus xanthoprymnus 



body temperature



We extend our thanks to D. Kolonkaya for the administrative management of the project. We are grateful to G. R. Michener for providing helpful comments on the field and laboratory studies. We thank the members of the Ünsal Family for their logistic support. We also thank E. Kart for assistance in the field and C. Y. Güngörmüş and H. Çakan for assistance in the laboratory. Funds for the project were provided by the Scientific and Technical Research Council of Turkey (TUBITAK, TBAG-104T279 Project). Preparation of this paper was partially supported by U.S. National Science Foundation grant IBN-0343917 to R. Refinetti.


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Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  • Mutlu Kart Gür
    • 1
  • Roberto Refinetti
    • 2
    Email author
  • Hakan Gür
    • 1
  1. 1.Department of Biology, Faculty of ScienceHacettepe UniversityAnkaraTurkey
  2. 2.Circadian Rhythm LaboratoryUniversity of South CarolinaWalterboroUSA

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